Field of the Invention
The invention relates in general to a memory device and the method for fabricating the same, and more particularly to a three-dimensional (3D) memory device and the method for fabricating the same.
Description of the Related Art
A 3D memory device, such as a 3D flash memory device having a single gate, a double gate or a surrounding gate, that includes a 3D memory cell array having vertical channels formed in a multi-layer stack and possesses a higher memory density and excellent electrical characteristics, e.g. reliability in data storage and high operating speed has been widespreadly adopted by portable audiovisual entertainment devices, cell phones or digital cameras etc.
Recently, the demands for a 3D memory device tends to be smaller in size and larger memory capacity. In order to provide a 3D memory device having larger memory density, the critical size of the multi-layer stack should be shrank. However, as the shrinkage of the critical size, it is harder to manufacture a 3D memory device due to rapidly increasing process complexity. In addition, the performance and reliability of the 3D memory device could be deteriorated by the program/erase interference occurring between two adjacent memory cells formed in the multi-layer stack due to the shrinkage of the critical size.
Therefore, there is a need of providing a 3D memory device and the method for fabricating the same to obviate the drawbacks encountered from the prior art.